A device for separating fluid mixtures, in particular for separating water from oil, includes a vacuum container (10) with several sub-chambers (26, 44, 40). At least one liquid constituent of the fluid mixture can be transported from the vacuum container after separation, by a transport device (12). The other constituents can be extracted from the vacuum container (10) in the form of gas and/or steam, using a vacuum pump (20). One of the sub-chambers (26) of the vacuum container (10) houses a heating device (28, 30), which heats the fluid mixture. The fluid mixture is guided into an additional sub-chamber (40), and is separated into its constituents by traversing a packed bed. Even cold and consequently viscous fluid mixtures can be supplied, due to the heating device, for separation inside the aforementioned vacuum container.